In carrying out this kind of measurement, in order to attain consistent conditions for measurement of the spectrum of light transmitted through or reflected from the target part of the living body, it is generally necessary to perform measurement by positioning the target part of the living body at a predetermined position relative to a light projecting member and/or a light receiving element for receiving the transmitted or reflected light.
Hitherto, for biological information measurement, the use has been made of a clip-type probe for biological information measurement of a biological information measuring probe secured to the target part of the living body by the use of a double-adhesive tape (such as disclosed in, for example, the Japanese Laid-open Patent Publication No. 6-14906). During the biological information measurement using the clip-type biological information measuring probe, the target part of the living body is sandwiched by a spring mechanism between one clip member embedded with a light emitting element, and another clip member embedded with a light receiving element, such that light emitted from the light emitting element and transmitted through the target part of the living body is received by the light receiving element to accomplish biological information measurement. On the other hand, during the biological information measurement using the double-sided adhesive tape, a light emitting element and a light receiving element are secured in position by the use of the double-sided adhesive tape so as to confront with each other with the target part of the living body intervening therebetween so that, as is the case with the clip-type system, light emitted from the light emitting element and transmitted through the target part of the living body can be received by the light receiving element to accomplish the biological information measurement.